Results 1  10
of
33
Multilevel graph layout on the GPU
 IEEE TRANS. VIS. COMPUT. GRAPH
, 2007
"... This paper presents a new algorithm for force directed graph layout on the GPU. The algorithm, whose goal is to compute layouts accurately and quickly, has two contributions. The first contribution is proposing a general multilevel scheme, which is based on spectral partitioning. The second contri ..."
Abstract

Cited by 32 (1 self)
 Add to MetaCart
This paper presents a new algorithm for force directed graph layout on the GPU. The algorithm, whose goal is to compute layouts accurately and quickly, has two contributions. The first contribution is proposing a general multilevel scheme, which is based on spectral partitioning. The second contribution is computing the layout on the GPU. Since the GPU requires a data parallel programming model, the challenge is devising a mapping of a naturally unstructured graph into a wellpartitioned structured one. This is done by computing a balanced partitioning of a general graph. This algorithm provides a general multilevel scheme, which has the potential to be used not only for computation on the GPU, but also on emerging multicore architectures. The algorithm manages to compute high quality layouts of large graphs in a fraction of the time required by existing algorithms of similar quality. An application for visualization of the topologies of ISP (Internet Service Provider) networks is presented. Index Terms—Graph layout, GPU, graph partitioning.
Direct forcing for lagrangian rigidfluid coupling
 IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS
, 2008
"... We propose a novel boundary handling algorithm for particlebased fluids. Based on a predictorcorrector scheme for both velocity and position, one and twoway coupling with rigid bodies can be realized. The proposed algorithm offers significant improvements over existing penaltybased approaches. ..."
Abstract

Cited by 23 (3 self)
 Add to MetaCart
(Show Context)
We propose a novel boundary handling algorithm for particlebased fluids. Based on a predictorcorrector scheme for both velocity and position, one and twoway coupling with rigid bodies can be realized. The proposed algorithm offers significant improvements over existing penaltybased approaches. Different slip conditions can be realized and nonpenetration is enforced. Direct forcing is employed to meet the desired boundary conditions and to ensure valid states after each simulation step. We have performed various experiments in 2D and 3D. They illustrate one and twoway coupling of rigid bodies and fluids, the effects of hydrostatic and dynamic forces on a rigid body as well as different slip conditions. Numerical experiments and performance measurements are provided.
CUDA implementation of a navierstokes solver on multigpu desktop platforms for incompressible flows
 in Proceedings of the 47th AIAA Aerospace Sciences Meeting, 2009
"... Graphics processor units (GPU) that are traditionally designed for graphics rendering have emerged as massivelyparallel "coprocessors " to the central processing unit (CPU). Smallfootprint desktop supercomputers with hundreds of cores that can deliver teraflops peak performance at the p ..."
Abstract

Cited by 23 (1 self)
 Add to MetaCart
Graphics processor units (GPU) that are traditionally designed for graphics rendering have emerged as massivelyparallel "coprocessors " to the central processing unit (CPU). Smallfootprint desktop supercomputers with hundreds of cores that can deliver teraflops peak performance at the price of conventional workstations have been realized. A computational fluid dynamics (CFD) simulation capability with rapid computational turnaround time has the potential to transform engineering analysis and design optimization procedures. We describe the implementation of a NavierStokes solver for incompressible fluid flow using desktop platforms equipped with multiGPUs. Specifically, NVIDIA’s Compute Unified Device Architecture (CUDA) programming model is used to implement the discretized form of the governing equations. The projection algorithm to solve the incompressible fluid flow equations is divided into distinct CUDA kernels, and a unique implementation that exploits the memory hierarchy of the CUDA programming model is suggested. Using a quadGPU platform, we observe two orders of magnitude speedup relative to a serial CPU implementation. Our results demonstrate that multiGPU desktops can serve as a costeffective smallfootprint parallel computing platform to accelerate CFD simulations substantially. I.
Fast hydraulic erosion simulation and visualization on gpu
 In Pacific Graphics
, 2007
"... Figure 1. Illustration of our erosion simulation on a ”PG”shaped mountain. (a) The initial terrain. (b) Terrain is being eroded by rainfall. The dissolved soil (denoted by green color) is transported by the water flow (blue). (c) The eroded terrain and the deposited sediment (red) after the rainfal ..."
Abstract

Cited by 12 (0 self)
 Add to MetaCart
(Show Context)
Figure 1. Illustration of our erosion simulation on a ”PG”shaped mountain. (a) The initial terrain. (b) Terrain is being eroded by rainfall. The dissolved soil (denoted by green color) is transported by the water flow (blue). (c) The eroded terrain and the deposited sediment (red) after the rainfall and during the evaporation. Natural mountains and valleys are gradually eroded by rainfall and river flows. Physicallybased modeling of this complex phenomenon is a major concern in producing realistic synthesized terrains. However, despite some recent improvements, existing algorithms are still computationally expensive, leading to a timeconsuming process fairly impractical for terrain designers and 3D artists. In this paper, we present a new method to model the hydraulic erosion phenomenon which runs at interactive rates on today’s computers. The method is based on the velocity field of the running water, which is created with an efficient shallowwater fluid model. The velocity field is used to calculate the erosion and deposition process, and the sediment transportation process. The method has been carefully designed to be implemented totally on GPU, and thus takes full advantage of the parallelism of current graphics hardware. Results from experiments demonstrate that the proposed method is effective and efficient. It can create realistic erosion effects by rainfall and river flows, and produce fast simulation results for terrains with large sizes. 1.
A Network Architecture Supporting Consistent Rich Behaviour in Collaborative Interactive Applications
"... Abstract — Network architectures for collaborative virtual reality have traditionally been dominated by client–server and peertopeer approaches, with peertopeer strategies typically being favoured where minimising latency is a priority, and client–server where consistency is key. With increasingl ..."
Abstract

Cited by 11 (0 self)
 Add to MetaCart
(Show Context)
Abstract — Network architectures for collaborative virtual reality have traditionally been dominated by client–server and peertopeer approaches, with peertopeer strategies typically being favoured where minimising latency is a priority, and client–server where consistency is key. With increasingly sophisticated behaviour models, and the demand for better support for haptics, we argue that neither approach provides sufficient support for these scenarios and thus a hybrid architecture is required. We discuss the relative performance of different distribution strategies in the face of real network conditions, and illustrate the problems they face. Finally we present an architecture that successfully meets many of these challenges, and demonstrate its use in a distributed virtual prototyping application which supports simultaneous collaboration for assembly, maintenance and training applications utilising haptics.
Simulation of large crowds in emergency situations including gaseous phenomena
 in CGI ’05: Proceedings of the Computer Graphics International 2005
"... Crowd animation and simulation have been widely studied over the last decade for many purposes: populating collaborative virtual environments, entertainment and special effects industry and finally simulating behaviors and motion of people in emergency situations for safety systems. This last topic ..."
Abstract

Cited by 11 (0 self)
 Add to MetaCart
(Show Context)
Crowd animation and simulation have been widely studied over the last decade for many purposes: populating collaborative virtual environments, entertainment and special effects industry and finally simulating behaviors and motion of people in emergency situations for safety systems. This last topic is addressed in this paper. We propose an original enhancement of a well known physicsbased animation model which allows to consider influence of gaseous phenomena such as smoke or toxic gases in the behavior of the crowd. In order to get real time performances we also propose an implementation of this framework on modern graphics hardware, which allows to simulate crowds of thousands individuals at interactive framerate. 1
How to solve systems of conservation laws numerically using the graphics processor as a highperformance computational engine
 Quak (Eds.), Geometric Modelling, Numerical Simulation, and Optimization: Industrial Mathematics at SINTEF
, 2005
"... Summary. The paper has two main themes: The first theme is to give the reader an introduction to modern methods for systems of conservation laws. To this end, we start by introducing two classical schemes, the Lax–Friedrichs scheme and the Lax–Wendroff scheme. Using a simple example, we show how the ..."
Abstract

Cited by 9 (2 self)
 Add to MetaCart
(Show Context)
Summary. The paper has two main themes: The first theme is to give the reader an introduction to modern methods for systems of conservation laws. To this end, we start by introducing two classical schemes, the Lax–Friedrichs scheme and the Lax–Wendroff scheme. Using a simple example, we show how these two schemes fail to give accurate approximations to solutions containing discontinuities. We then introduce a general class of semidiscrete finitevolume schemes that are designed to produce accurate resolution of both smooth and nonsmooth parts of the solution. Using this special class we wish to introduce the reader to the basic principles used to design modern highresolution schemes. As examples of systems of conservation laws, we consider the shallowwater equations for water waves and the Euler equations for the dynamics of an ideal gas. The second theme in the paper is how programmable graphics processor units (GPUs or graphics cards) can be used to efficiently compute numerical solutions of these systems. In contrast to instruction driven microprocessors (CPUs), GPUs subscribe to the datastreambased computing paradigm and have been optimised for high throughput of large data streams. Most modern numerical methods for hyperbolic conservation laws are explicit schemes defined over a grid, in which the unknowns at each grid point or in each grid cell can be updated independently of the others. Therefore such methods are particularly attractive for implementation using datastreambased processing. 1
Hydrometra Simulation for VRBased Hysteroscopy Training
"... Abstract. During hysteroscopy a hydrometra is maintained, i.e. the uterus is distended with liquid media to access and visualize the uterine cavity. The pressure and flow induced by the liquid are crucial tools for the gynecologists during surgery to obtain a clear view of the operation site. This p ..."
Abstract

Cited by 3 (1 self)
 Add to MetaCart
(Show Context)
Abstract. During hysteroscopy a hydrometra is maintained, i.e. the uterus is distended with liquid media to access and visualize the uterine cavity. The pressure and flow induced by the liquid are crucial tools for the gynecologists during surgery to obtain a clear view of the operation site. This paper presents two different aspects of hydrometra simulation, namely the distension of the uterine muscle and the liquid flow simulation in the cavity. The deformation of the organ’s shape is computed offline based on finite element calculations whereas the flow is approximated on the fly by solving the simplified NavierStokes equations. The realtime capabilities of the presented algorithms as well as the level of fidelity achieved by the proposed methods are discussed. 1
HardwareAccelerated Simulated Radiography
"... Figure 1: (a) A fuel capsule for inertial confinement fusion showing the fill tube by which Hydrogen fuel is injected. (b) Simulations and experiments indicate that during capsule compression the fill tube may cause a jet to form that may lead to reduced yield. (c) Simulated radiographs are used to ..."
Abstract

Cited by 3 (0 self)
 Add to MetaCart
(Show Context)
Figure 1: (a) A fuel capsule for inertial confinement fusion showing the fill tube by which Hydrogen fuel is injected. (b) Simulations and experiments indicate that during capsule compression the fill tube may cause a jet to form that may lead to reduced yield. (c) Simulated radiographs are used to design diagnostics that can detect the jet during experiments and lead to quantitative measurements of position and velocity. We present the application of hardware accelerated volume rendering algorithms to the simulation of radiographs as an aid to scientists designing experiments, validating simulation codes, and understanding experimental data. The techniques presented take advantage of 32bit floating point texture capabilities to obtain solutions to the radiative transport equation for Xrays. The hardware accelerated solutions are accurate enough to enable scientists to explore the experimental design space with greater efficiency than the methods currently in use. An unsorted hexahedron projection algorithm is presented for curvilinear hexahedral meshes that produces simulated radiographs in the absorptiononly regime. A sorted tetrahedral projection algorithm is presented that simulates radiographs of emissive materials. We apply the tetrahedral projection algorithm to the simulation of experimental diagnostics for inertial confinement fusion experiments on a laser at the University of Rochester.
Computational fluid dynamics for indoor environment modeling: Past, present, and future
 In: Proceedings of the 6th International Indoor Air Quality, Ventilation and Energy Conservation in Buildings Conference (IAQVEC 2007
, 2007
"... This paper gave an overview of the past and present applications of various Computational Fluid Dynamics (CFD) methods for indoor environment modeling. Typical applications used the CFD to calculate airflow, air temperature, contaminant concentrations, and turbulence in enclosed environment for stud ..."
Abstract

Cited by 3 (1 self)
 Add to MetaCart
This paper gave an overview of the past and present applications of various Computational Fluid Dynamics (CFD) methods for indoor environment modeling. Typical applications used the CFD to calculate airflow, air temperature, contaminant concentrations, and turbulence in enclosed environment for studying or designing thermal comfort and indoor air quality. With simple airflow and geometry, the CFD is capable of calculating accurately mean flow parameters but less accurately turbulence parameters. For airflow in real indoor environment, it is very challenging to measure and calculate accurately the mean and turbulence flow parameters, because neither of them are free from errors. Thus, a complete validation of the CFD results by the corresponding experimental data obtained on site is extremely difficult. In the future, CFD applications for indoor environment will deal with more complicated dynamic problems and will require a method for faster than real time simulations of airflow. The Fast Fluid Dynamics (FFD) can dramatically enhance the computing speed. By running the FFD on GPUs, it is possible to perform faster than real time simulations of airflow in indoor environment.